1. Technical Field
The present invention relates to a fire suppression system activated manually (such as by a pull knob or electronically) or activated automatically (such as by the detection links in the detection line).
2. Related Art
Fire suppression systems may be activated using a pull knob. The pull knob may be located in the path of egress or near an operator of a machine, such as an oven, popcorn machine, etc., and may be used to activate the fire suppression system. In the event of a fire, the operator may pull the pull knob, thereby activating a release mechanism of the fire suppression system.
The release mechanism may indirectly or directly cause the fire suppression agent to be dispensed, thereby reducing or eliminate the fire. For example, FIG. 1 illustrates a fire suppression system 100 that using a pull handle 116 to activate a release mechanism 160. Specifically, the wire rope 140 may be connected between pull handle 116 and an oval sleeve 170 of the cable lever 190 of release mechanism 160. The oval sleeve 170 may be used to make a loop in the rope so that the connection is between the pull handle 116 and cable lever 190 of the release mechanism 160. The pull handle 116 may be part of a pull station 110, that includes a faceplate 114 and pull knob body 118, and is located in an area remote from hot oil kitchen apparatuses, such as oil fryer ovens. The color of the faceplate 114 is a brushed stainless color in order to blend with the kitchen apparatuses, etc. In the event of a flash fire on the hot oil surface, the operator may pull the pull handle 116, thereby activating the release mechanism 160 located within the system pressurizing control cabinet 162. The release mechanism 160 thereafter indirectly causes release of the fire suppression agent by creating a pressure surge into a container of fire suppression agent, such as foam or flame retardant material, which in turn causes a release of the fire suppression agent onto the flaming oil through permanently placed spray nozzles, and thus reducing or extinguishing the fire. Alternatively, the release mechanism may directly cause release of the fire suppression agent, such as the pull handle 116 activating a triggering release mechanism coupled directly to a fire suppression agent container such as a water container or such as a CO2 fire extinguisher. Upon activation, water may be dispensed. Or, the CO2 fire extinguisher (or other extinguishing agent) may discharge CO2 (or nitrogen cartridges) to cause the pressurization of the agent, thereby expelling the agent through a fixed piping system into the containment area to eliminate the fire supporting O2 and thus minimizing or extinguishing the fire. Alternatively, CO2 may be used as the extinguishing agent
The pull handle in the fire suppression system is coupled to the release mechanism. One way to couple the pull handle 116 to the release mechanism 160 is by using a rigid conduit mechanical system, such as shown in FIG. 1. A wire rope 140 is routed from the system pressurizing control cabinet 162 to the pull station 110 through rigid electrical mechanical tubing (EMT) 130 and making 90 degree turns through pulley elbows 150. Further, the rigid EMT 130 is connected to a junction box 120 via a conduit-to-junction box coupling 131 to the pull station 110. However, using rigid EMT tubing 130 and 90 degree elbows 150 is very labor intensive, expensive and not preferable to some building wall geometries and accesses.
Another way to couple the pull handle to the release mechanism is to route the wire rope 140 through an outer diameter (OD) (such as a ¼″ diameter) pre-shaped rigid conduit tubing. The pre-shaped rigid conduit tubing is commonly used in situations like the popcorn machine because designs and component dimensions are known and fixed. The pre-shaped rigid tubing may be constructed using aluminum or stainless steel for example, to ensure that in the event of a fire, the wire rope 140 routing conduit is non-flammable and will function as designed under high heat conditions. Because the pre-shaped rigid conduit tubing does not include pulley elbows 150, the wire rope 140 encounters high friction, making pulling of the pull handle difficult.
Still another way to couple the pull handle to the release mechanism is to route the wire rope along a predetermined path (length and direction) defined by specific pulley systems located at each change in wire rope direction. Disadvantages to this method include the excess cost associated with the pulley system along with the lack of controlled routing. A simple loss of wire rope tension might result in the wire rope “jumping its pulley” and thus a complete failure of the wire rope system.
Yet another way to couple the pull handle to the release mechanism is by using a pneumatic system. The pull handle may trigger a change is gas pressure, thereby activating the release mechanism. While the pneumatic system may be easier to configure than the systems using the electrical EMT tubing 130 and the 90 degree pulley elbows 150 shown in FIG. 1 or the pre-shaped rigid conduit tubing, it is typically less reliable. Therefore, what is needed is an easily configurable and reliable system for activating a release mechanism of a fire suppression using a pull handle.
As discussed above, the pull handle 116 is part of a pull station 110. An example of a pull station 110 is illustrated in FIGS. 2, 3 and 4A-C. Configuration of the pull station 110 may include installing a break rod 112, as shown in FIGS. 4A-C. The break rod 112 is slid through break rod end bushings 113 until a set-screw end bushing 119 is screwed into break rod end bushing 113. However, sliding the break rod 112 into the break rod end bushings 113 may prove difficult. Further, pulling the pull handle 116 from the pull knob bushing 125 after installation of the break rod 112 may also prove difficult. The pull station 110 is illustrated in cross-section with the pull handle 116 connected (FIG. 2) and disconnected (FIG. 3). Due to the design, excess force is required when pulling in direction 134 to overcome the friction forces resulting from cable friction at friction points such as 132 and 133 shown in FIGS. 2 and 3. What is therefore needed is a pull station that is easier to configure and to activate.